{"title":"Foldameric receptors with domain-swapping cavities capable of selectively binding and transporting monosaccharides.","authors":"Geunmoo Song, Seungwon Lee, Kyu-Sung Jeong","doi":"10.1039/d4ob02061h","DOIUrl":null,"url":null,"abstract":"<p><p>The development of synthetic receptors capable of selectively binding and transporting saccharides is crucial but highly challenging. In this study, two foldameric receptors 1 and 2, consisting of two repeating monomers, indolocarbazole and naphthyridine units, with different aromatic spacers in the middle of their sequences, have been synthesised. These receptors fold into helical conformations, and the two strands of each receptor are assembled to create domain-swapping cavities for binding monosaccharides by multiple hydrogen bonds. According to <sup>1</sup>H NMR, CD spectroscopy, mass spectrometry, and ITC experiments, receptor 1 forms two distinct 2 : 2 complexes with methyl β-D-galactopyranoside and methyl β-D-glucopyranoside: (1-<i>MM</i>)<sub>2</sub>⊃(methyl β-D-galactopyranoside·2H<sub>2</sub>O)<sub>2</sub> and (1-<i>MP</i>)<sub>2</sub>⊃(methyl β-D-glucopyranoside)<sub>2</sub>. Despite being composed of identical foldamer strands, these two complexes exhibit notably different folding and assembly modes to achieve optimal stability. The binding affinities of 1 for methyl β-D-galactopyranoside and methyl β-D-glucopyranoside are estimated to be log <i>K</i> = 12.7 and 13.3, respectively, in 5% (v/v) DMSO/CH<sub>2</sub>Cl<sub>2</sub>. On the other hand, receptor 2 forms a stable 2 : 2 receptor/guest complex with methyl β-D-glucopyranoside, (2-<i>MP</i>)<sub>2</sub>⊃(methyl β-D-glucopyranoside)<sub>2</sub>, with an association constant of log <i>K</i> = 13.9, which is significantly higher than that of methyl β-D-galactopyranoside (log <i>K</i> = 11.1) and methyl α-D-glucopyranoside (log <i>K</i> = 10.6). Furthermore, receptor 2 facilitates the selective transport of methyl β-D-glucopyranoside over other glycosides across an organic phase (CH<sub>2</sub>Cl<sub>2</sub>) in U-tube experiments.</p>","PeriodicalId":96,"journal":{"name":"Organic & Biomolecular Chemistry","volume":" ","pages":""},"PeriodicalIF":2.9000,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Organic & Biomolecular Chemistry","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.1039/d4ob02061h","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, ORGANIC","Score":null,"Total":0}
引用次数: 0
Abstract
The development of synthetic receptors capable of selectively binding and transporting saccharides is crucial but highly challenging. In this study, two foldameric receptors 1 and 2, consisting of two repeating monomers, indolocarbazole and naphthyridine units, with different aromatic spacers in the middle of their sequences, have been synthesised. These receptors fold into helical conformations, and the two strands of each receptor are assembled to create domain-swapping cavities for binding monosaccharides by multiple hydrogen bonds. According to 1H NMR, CD spectroscopy, mass spectrometry, and ITC experiments, receptor 1 forms two distinct 2 : 2 complexes with methyl β-D-galactopyranoside and methyl β-D-glucopyranoside: (1-MM)2⊃(methyl β-D-galactopyranoside·2H2O)2 and (1-MP)2⊃(methyl β-D-glucopyranoside)2. Despite being composed of identical foldamer strands, these two complexes exhibit notably different folding and assembly modes to achieve optimal stability. The binding affinities of 1 for methyl β-D-galactopyranoside and methyl β-D-glucopyranoside are estimated to be log K = 12.7 and 13.3, respectively, in 5% (v/v) DMSO/CH2Cl2. On the other hand, receptor 2 forms a stable 2 : 2 receptor/guest complex with methyl β-D-glucopyranoside, (2-MP)2⊃(methyl β-D-glucopyranoside)2, with an association constant of log K = 13.9, which is significantly higher than that of methyl β-D-galactopyranoside (log K = 11.1) and methyl α-D-glucopyranoside (log K = 10.6). Furthermore, receptor 2 facilitates the selective transport of methyl β-D-glucopyranoside over other glycosides across an organic phase (CH2Cl2) in U-tube experiments.
期刊介绍:
Organic & Biomolecular Chemistry is an international journal using integrated research in chemistry-organic chemistry. Founded in 2003 by the Royal Society of Chemistry, the journal is published in Semimonthly issues and has been indexed by SCIE, a leading international database. The journal focuses on the key research and cutting-edge progress in the field of chemistry-organic chemistry, publishes and reports the research results in this field in a timely manner, and is committed to becoming a window and platform for rapid academic exchanges among peers in this field. The journal's impact factor in 2023 is 2.9, and its CiteScore is 5.5.